1. Field of the Invention
The present invention relates to a scanner, and more particularly, to a scanner which takes samples from different positions of a document to increase its resolution.
2. Description of the Prior Art
A scanning module of a prior art scanner comprises a set of linearly arranged sampling units for scanning a document. The resolution of such a scanner is determined by the distance between two neighboring sampling units. A smaller distance is associated with a higher resolution. If a user wants to increase the resolution of the scanner, the user has to replace the scanning module by one which has a higher resolution. Because the distance between two neighboring sampling units of a high resolution scanning module is shorter than a low resolution scanning module, and the number of sampling units of a scanning module is proportional to its resolution, it becomes quite expensive to manufacture a high resolution scanning module.